Functional Hardware Emulation (Stream Free Running HLS C/C++ Kernel)¶

This example demonstrates how a user can run functional model of HLS kernel in HW Emulation.

KEY CONCEPTS: Emulation Functional mode

This example demonstrates the simulation of HLS C/C++ streaming free running kernel in functional mode. The functional mode in v++ generates the SCTLM code for the HLS kernel. HW Emulation is mainly targeted for HW Kernel Debug with detailed, cycle accurate view of kernel activity and functional model is an advanced use case when user wants to speedup the emulation by compiling desired kernels in functional mode. In this example, there are two stream free running HLS kernels out of which increment_func is compiled in functional mode and increment_rtl is compiled as default RTL during hardware emulation.

XO generation¶

During v++ compile flow, while creating hw_emu XO, the user provides a switch describing the intention to do a functional simulation that will generate XO with the SystemC wrapper on C code.

Input from the user¶

Create a config file config <hw_emu_func.cfg> with following advanced compiler options:

[advanced]
param=compiler.emulationMode=func

In the Makefile, add the following flag in the v++ flow while compiling kernel:

VPP_FLAGS_increment_func += --config hw_emu_func.cfg
increment_func.xo: increment_func.cpp
mkdir -p $(TEMP_DIR)
$(VPP) $(VPP_FLAGS) $(VPP_FLAGS_increment1) -c -k increment_func --temp_dir $(TEMP_DIR)  -I'$(<D)' -o'$@' '$<'

DESIGN FILES¶

Application code is located in the src directory. Accelerator binary files will be compiled to the xclbin directory. The xclbin directory is required by the Makefile and its contents will be filled during compilation. A listing of all the files in this example is shown below

src/host.cpp
src/increment_func.cpp
src/increment_rtl.cpp
src/mem_read1.cpp
src/mem_read2.cpp
src/mem_write1.cpp
src/mem_write2.cpp

Access these files in the github repo by clicking here.

COMMAND LINE ARGUMENTS¶

Once the environment has been configured, the application can be executed by

./stream_func_mode <krnl_incr XCLBIN>